package com.telcordia.cvas.rpn;


public class RpnCalculator {
	private OperandStack values = new OperandStack();

	public int getXRegister() {
		return values.peek();
	}

	public void setXRegister(int value) {
		values.replaceTop(value);
	}

	public void enter() {
		values.push(getXRegister());
	}

	public void add() {
		new Add().execute(values);
	}

	public void subtract() {
		new Subtract().execute(values);
	}

	public void factorial() {
		new Factorial().execute(values);
	}

	public void perform(String operatorName) {
		add();
	}

}
